The Value of Quantitative EEG

There has been a huge increase in awareness of post-concussion syndrome (PCS) in recent years. Those of us who work with people with PCS, as healthcare providers, researchers, lawyers or advocates, are encouraged by this. There have been more media stories, more prevention efforts, more research dollars, more conferences and workshops and more startups focused on PCS and traumatic brain injury (TBI) than ever before. We all agree that better diagnosis and treatment are urgently needed, and the number of people who need them is growing every day.

For people who are not sure whether they have PCS or not, and for those seeking treatment for their PCS, getting a functional brain test called a quantitative EEG (qEEG) is a good step to take. qEEG testing has been available for decades, but it has received renewed interest because of its potential role in TBI management.

For many, it provides the first clear and objective evidence that their symptoms are not just ‘in their heads’. When I review qEEG reports with patients, showing them the specific areas that are affected, I have seen tears well up in their eyes. In many cases, the most affected area corresponds exactly to the place where they were hit – or the place in their head where they feel the worst symptoms.

This simple test, which is safe, noninvasive, painless and relatively easy to do, offers a unique view of a person’s function that is based on the electrical activity of the brain. Psychologists, physicians and researchers use qEEG assessment to find and measure specific areas of the brain that produce abnormal patterns of electricity. In addition to PCS, this test can help diagnose and treat epilepsy and ADHD, and newer studies suggest it may be useful in depression, anxiety, PTSD and other disorders.

The 60-90 minute procedure is totally painless. Electrodes are applied to the skin on 19 points on the head – to measure electricity. That electricity comes from neurons firing in the brain, and contains data that sheds light on brain activity. The standard EEG is visually scanned by neurologists to identify the spikes that neurons produce during seizure activity. The qEEG, in contrast, is analyzed by computer software that breaks it down into millions of bits of data that are compared to average values for an age- and sex-matched group of healthy volunteers. This data can be used to identify the specific areas that are producing abnormal electricity, and the specific frequencies they produce.

Most experts would agree that an abnormal qEEG assessment report supports the clinical diagnosis of post-concussion syndrome. While it has been used as evidence in several US cases, its legal status in Canada remains inconclusive. In 2011, the Supreme Court of British Columbia deemed qEEG evidence presented in Bialkowski vs. Banfield to be inadmissable. The judge said his reason was that the medical expert in the case was a psychologist and not a neurologist. No one has ever used a qEEG assessment report as evidence in Ontario.

qEEG test results are also used to create a neurofeedback treatment plan. Neurofeedback, also called EEG biofeedback, allows treatment to target the most affected area and normalize the frequency that is most abnormal. If the right frontal lobe is overactive in the delta range (0-4 Hertz), it is trained down. If the left middle parietal lobe is underachieve in the alpha range (8-12 Hz), it is trained up.

Neurofeedback helps people learn to feel their way back to normal brain function. It is like meditating with a mirror. By connecting the brain to a computer that shows you what your brain is doing in real time, you can learn to adjust it at will. This occurs gradually, usually over a series of treatments that are done 2-3 times per week. It can also be combined with vision therapy, acupuncture, mindfulness training and other modalities that promote brain recovery.

Evidence supporting the effectiveness of neurofeedback in PCS is still preliminary. A systematic review by May et al was published in 2013 in the Annals of Clinical Psychiatry. They identified 22 published reports of its use in TBI, all of which were positive, but none were placebo-controlled randomized controlled trials. These are sure to come, as interest in the field grows.

One of our research interests is to figure out whether qEEG data can be used to identify the people who will not recover from their concussion. PCS is diagnosed at three months post-injury, and our experience has been that treatment outcomes are significantly worse in patients who have had symptoms for more than a year. This precious 3-12 month window is the best ideally be the time to start aggressive treatment to prevent complications. Our group has identified novel and specific abnormalities patients with longstanding PCS symptoms, which may lead to earlier diagnosis and more effective treatment.

Neurofeedback and qEEG assessment are available at specialized centres that treat brain-related and mental health disorders. Our centre has taken a leading role in making these innovative tools available to patients who need them. Insurers were cautious with early requests, but are now commonly approving this testing and treatment. While I am aware of my bias as a provider of this treatment, I think everyone who has had a concussion should have a qEEG.